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During the past few years, single‐atom catalysts (SACs) have attracted considerable attention in electrolysis due to their outstanding catalytic performance and efficient atomic utilization. SACs exhibit a simple structure, high catalytic activity, consistent scaling relationships for single sites, and low metal content but their practical applications are still limited. Dual single‐atom catalysts (DACs), which feature excellent selectivity, high atomic utilization efficiency, and remarkable stability, are emerging as new frontiers in heterogeneous electrocatalysis. They increase catalytic activity by promoting synergistic effects between metal‐active sites. In this paper, we present a comprehensive overview of the latest developments in dual‐atom catalysts for oxygen evolution reaction (OER) and oxygen reduction reaction (ORR). In addition, we explore the differences between homonuclear and heteronuclear configurations, the emergence of single/dual‐site metal catalysts, and the methods currently used for their synthesis. Lastly, this review discusses several perspectives for advancing the development of dual‐atom catalysts for OER and ORR electrocatalysis. [ABSTRACT FROM AUTHOR]

[Display omitted] • Advances in MXene-based materials for photo and electrocatalytic NO 3 - are highlighted. • Developments on MXenes for photo and electrocatalytic CO 2 are discussed. • Links between tuneable features of MXenes and their catalytic activities are discussed. • The key challenges and possibilities with MXene-based materials are also explored. Rapid industrialization and urban development release large amounts of toxic pollutants such as nitrate (NO 3 −) and CO 2 , which cause not only environmental issues but also offer reasons of sickness worldwide. Several methods have been devised to purify air and water in the past 2 decades but went futile because of high cost, low-performance, and cause secondary pollutants. Converting NO 3 − and CO 2 photochemically and electrochemically into energy-rich molecules and agro-boosters is an innovative strategy that can help with environmental remediation and meet the world's growing energy needs. However, these approaches require highly active, selective, and long-lasting catalysts. In this context, researchers have studied several smart and multifunctional materials for the reduction of NO 3 − and CO 2 pollutants into valuable chemicals. Among them, MXenes, a class of 2D materials composed of carbonitrides, carbides, and nitrides of transition metals, have gained attention because of their remarkable physico-chemical, mechanical, and electrochemical properties. However, quantization of MXenes for photo and electrocatalytic NO 3 − and CO 2 , reduction is required, and the lessons learned must be applied to future MXene-based materials. This article focuses primarily on the photocatalytic and electrocatalytic conversion of NO 3 − and CO 2 to value-added products, highlighting MXene-based catalysts, reaction intermediates, links between the tuneable properties of MXenes and their catalytic activities, research hurdles, and future prospects. [ABSTRACT FROM AUTHOR]